[
https://issues.apache.org/jira/browse/RNG-104?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16868448#comment-16868448
]
Alex D Herbert commented on RNG-104:
------------------------------------
{quote}I don't understand why you changed it
{quote}
The original estimate was a demonstration that the period is large enough. It
used a made up time of 0.1 nanoseconds per {{long}}. The new estimate uses the
time from the benchmark (15ns/long). That is the only difference.
I'll not do an estimate for array generation. Times are roughly 400 ns per 128
longs so 3.1 ns/long but this is without synchronisation overhead. That will
slow it down a bit.
I'll create a ticket to make the changes to the NumberFactory.
> SeedFactory seed creation performance analysis
> ----------------------------------------------
>
> Key: RNG-104
> URL: https://issues.apache.org/jira/browse/RNG-104
> Project: Commons RNG
> Issue Type: Task
> Components: simple
> Affects Versions: 1.3
> Reporter: Alex D Herbert
> Assignee: Alex D Herbert
> Priority: Minor
> Attachments: t1.jpg, t4.jpg, well_lock_vs_sync1.png,
> well_lock_vs_sync4.jpg, well_sync_performance.jpg,
> well_unfair_performance.jpg, well_unfair_vs_fair.jpg, xor_unfair_int1.png,
> xor_unfair_long1.png
>
>
> The SeedFactory is used to create seeds for the random generators. To ensure
> thread safety this uses synchronized blocks around a single generator. The
> current method only generates a single int or long per synchronisation.
> Analyze the performance of this approach. The analysis will investigate
> generating multiple values inside each synchronisation around the generator.
> This analysis will also investigate methods to supplement the SeedFactory
> with fast methods to create seeds. This will use a fast seeding method to
> generate a single long value. This can be a seed for a SplitMix generator
> used to create a seed of any length.
>
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
